The estimates from their best models show right-to-carry laws associated with increases in 7 of 9 crimes studied, with the largest effect (+9 percent) being the crime many researchers would have hypothesized would increase – aggravated assaults
The 'Right to Carry' Fallacy - Room for Debate - NYTimes.com
Some academic studies that have rejected Lott's conclusions include the following. These studies contend that there seems to be little or no effect on crime from the passage of license-to-carry laws. Donohue's 2003 study finds a temporary increase in aggravated assaults.
More Guns, Less Crime - Wikipedia, the free encyclopedia
1. Lott's study suffers from numerous methodological problems, which bias his results.
Lott does not properly control for factors, such as poverty, the illicit drug market, gang activity, which can affect crime. Lott uses methodology that was discredited over two decades ago by the National Academy of Sciences.
2. Lott does not prove that "more guns" cause "less crime", as implied by the title of his book. In fact, he provides no credible mechanism to describe this alleged phenomenon.
Were there more guns? Most surveys show either a decrease or no change in gun ownership. Since there aren't "more guns", Lott's entire argument is invalid. To find that the enactment of concealed-carry laws actually reduce crime, Lott assumes the following series of events:
"Shall-issue" law passes --> Increase number of permits issued --> Increase handgun carrying by citizens --> Increase use of handguns for self-defense against crime --> Criminal alter their behavior --> Change in rate and pattern of crime".
However, Lott investigates only the first and last steps in the process, providing little empirical evidence that any of the necessary intermediate steps occur as described above. Since many of these intermediate steps do not occur, as Lott assumes, Lott's conclusions fall short and can not be valid.
3. Lott avoids many implausible conclusions that can be obtained from his work.
According to Lott's data, middle-aged and elderly black women (as victims or perpetrators) have a greater effect on reducing the murder rate than young black males. Lott would have us believe that if law enforcement focused on the activities of middle-aged or elderly black women, we could dramatically reduce crime. Lott's data show that an increase in unemployment or a decrease in income level reduces crime. The data imply that we could reduce crime by firing people from their jobs.
Gunfree on Lott